pkt_sched: Add qdisc->ops->peek() implementation.

Add qdisc->ops->peek() implementation for work-conserving qdiscs.
With feedback from Patrick McHardy.

Signed-off-by: Jarek Poplawski <jarkao2@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 10 insertions, 0 deletions

diff --git a/net/sched/sch_atm.c b/net/sched/sch_atm.c
index 43d37256c15e..f9eac0818d18 100644
--- a/net/sched/sch_atm.c
+++ b/net/sched/sch_atm.c
@@ -522,6 +522,15 @@ static struct sk_buff *atm_tc_dequeue(struct Qdisc *sch)
         return skb;
 }
 
+static struct sk_buff *atm_tc_peek(struct Qdisc *sch)
+{
+        struct atm_qdisc_data *p = qdisc_priv(sch);
+
+        pr_debug("atm_tc_peek(sch %p,[qdisc %p])\n", sch, p);
+
+        return p->link.q->ops->peek(p->link.q);
+}
+
 static int atm_tc_requeue(struct sk_buff *skb, struct Qdisc *sch)
 {
         struct atm_qdisc_data *p = qdisc_priv(sch);
@@ -694,6 +703,7 @@ static struct Qdisc_ops atm_qdisc_ops __read_mostly = {
         .priv_size      = sizeof(struct atm_qdisc_data),
         .enqueue        = atm_tc_enqueue,
         .dequeue        = atm_tc_dequeue,
+        .peek           = atm_tc_peek,
         .requeue        = atm_tc_requeue,
         .drop           = atm_tc_drop,
         .init           = atm_tc_init,